The policy had previously been proposed to and rejected by the Bush administration, which said it was the wrong tool to be using. The proposal lists the negative effects of global warming, including longer and hotter heat waves, increased flooding, and the increased spread of diseases due to warmer weather.

EPA administrator Lisa Jackson has previously suggested declaring global warming a health threat, and that the agency could use the 1970 Clean Air Act to use to combat it.

Environmental groups applauded the finding, with the director of Clean Air Watch, Frank O’Donnell, calling it “a green-letter day for the environment.”

One of the U.S. Chamber of Commerce vice presidents, William L. Kovacs, said if the the proposal is put into effect that it “will be devastating to the economy.”

It is unclear whether the Obama administration will go along with the proposal. White House spokesman Ben LaBolt commented that “The president has made clear that to combat climate change, his strong preference is for Congress to pass energy security legislation that includes a cap on greenhouse gas emissions.” No specific timeline has been given for when a decision would be made.

An upcoming conference in Copenhagen, Denmark will focus on drawing up a new international global warming treaty, which the United States plans to attend, a clear reversal from the Bush administration’s non-participation in the 1997 Kyoto Protocol.